大白猪不同脂肪部位脂质代谢相关基因的表达差异分析

Analysis of Different Expression of Lipid Metabolism Related Genes in Different Fat Parts of Large White Pigs

脂肪沉积决定于脂肪酸合成、转运和分解代谢的动态平衡。为比较猪(Sus scrofa domesticus)不同脂肪部位脂质代谢差异和不同性别间的差别,筛选与脂肪沉积能力显著关联的相关酶基因,本研究检测大白猪(Large White pigs)脂质代谢相关生化指标、肌内脂肪(intramuscular fat)含量,皮下脂肪、腹部脂肪和肾周脂肪组织间脂肪酸合成酶基因ACC,脂肪酸转运酶基因CPT1A和CD36,以及脂肪酸分解酶基因HSL和LPL的转录表达水平,分析目标基因与血清生化指标和肌内脂肪含量的相关性,比较在不同脂肪组织间的基因表达差异。结果表明,血清甘油三酯(triglycerides)、总胆固醇(total cholesterol)和肌内脂肪含量在不同性别大白猪中均无显著性差异(P>0.05)。相关性分析表明,大白猪公猪腹部脂肪中ACC基因表达量与甘油三酯含量呈显著正相关(P<0.05),皮下脂肪中HSL基因表达量与甘油三酯含量呈显著负相关(P<0.05);大白猪母猪腹部脂肪中ACC基因表达量与甘油三酯含量呈极显著正相关(P<0.01)。实时定量PCR结果表明,在大白猪公猪中,ACC基因在腹部脂肪中的表达丰度最高;CPT1A基因在腹部脂肪中的表达量极显著高于皮下脂肪和肾周脂肪的(P<0.01);LPL基因在肾周脂肪中的表达量极显著高于腹部脂肪和皮下脂肪的(P<0.01);CD36基因和HSL基因在不同脂肪组织中未见显著差异(P>0.05)。在大白猪母猪中,ACC基因在腹部脂肪中的表达丰度最高;CPT1A基因和HSL基因在皮下脂肪中的表达量极显著低于腹部脂肪的(P<0.01),显著低于肾周脂肪的(P<0.05);CD36基因在皮下脂肪中的表达量极显著低于腹部脂肪和肾周脂肪的(P<0.01);LPL基因在不同脂肪组织中未见显著差异(P>0.05)。本研究初步揭示了不同性别大白猪脂质代谢相关基因在不同脂肪部位的表达差异,提示ACC基因可能正向调控腹部脂肪沉积,HSL基因在大白猪公猪皮下脂肪分解代谢中可能发挥更重要的功能。

Fat deposition is determined by the dynamic balance of fatty acid synthesis,transport and catabolism.In order to compare the differences of lipid metabolism in different fat parts of pigs(Sus scrofa domesticus)and the differences between different genders,the relevant enzyme genes that are significantly associated with fat deposition capacity,the lipid metabolism-related biochemical indices and intramuscular fat(intramuscular fat)content of Large White pigs,and transcription expression levels of fatty acid synthetase gene ACC,fatty acid transportase gene CPT1A and CD36,fatty acid decompose enzyme gene HSL and LPL were detected in subcutaneous fat,abdominal fat,and perirenal fat tissues.The correlation between the target gene and serum biochemical indexes and intramuscular fat content was analyzed,and the difference of gene expression in different adipose tissues was compared.The results showed that there were no significant differences in the contents of serum triglyceride,total cholesterol and intramuscular fat among male and female Large White pigs(P>0.05).Correlation analysis showed that ACC gene expression level in abdominal fat was significantly positively correlated with triglycerides content(P<0.05),while HSL gene expression level in subcutaneous fat was significantly negatively correlated with triglycerides content(P<0.05).ACC gene expression in abdominal fat of Large White sows was positively correlated with triglycerides content(P<0.01).Real time quantitative PCR results showed that the expression abundance of ACC gene in abdominal fat was the highest in Large White boars.The expression of CPT1A gene in abdominal fat was significantly higher than that in subcutaneous fat and perirenal fat(P<0.01).The expression of LPL gene in perirenal fat was significantly higher than that in abdominal fat and subcutaneous fat(P<0.01).There was no significant difference between CD36 gene and HSL gene in different adipose tissues(P>0.05).The expression abundance of ACC gene in abdominal fat was the highest in Large White sows.The expression levels of CPT1A gene and HSL gene in subcutaneous fat were significantly lower than those in abdominal fat(P<0.01),and significantly lower than those in perirenal fat(P<0.05).The expression of CD36 gene in subcutaneous fat was significantly lower than that in abdominal fat and perirenal fat(P<0.01).There was no significant difference in LPL gene among different adipose tissues(P>0.05).This study preliminarily revealed the differential expression of lipid metabolism related genes in different fat parts of different genders of Large White pigs,suggesting that the ACC gene may positively regulate abdominal fat deposition,and the HSL gene may play a more important role in subcutaneous fat breakdown metabolism in male Large White pig.